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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Bridging Component Models and Integration problems

Gelber, Natan January 2006 (has links)
<p>Component based software engineering promotes the use of software component as a cor-</p><p>ner stone for new software. Taken from other manufacturing fields, the vision of selecting</p><p>the components needed and building them as Lego to create a new software seems to of-</p><p>fer enormous advantages for software development. Worldwide, industry and scholars are</p><p>trying to remove the obstacles obstructing this course of action. This report names some</p><p>of the problems that software integrators and developers face. It concentrates on low-level</p><p>communication and other aspects of integration problems. it is based upon practical and</p><p>theoretical research. the conclusion of the report is that while each problem can be solved</p><p>in and of itself, these solutions often lead to the creation of new problems, and therefore</p><p>leave ample room for further research.</p>
52

Understanding international efforts to address the humanitarian impacts of cluster munitions, 2003-08

Borrie, John Patrick January 2012 (has links)
This thesis examines the evolution of international humanitarian concern culminating in adoption of a Convention on Cluster Munitions (CCM) banning these weapons in May 2008. It is based on systematic analysis of official documents, extensive interviews, participant-observation, and several bodies of international relations (IR) theory. Part I explains the research methodology and discusses the theoretical context for the thesis. It is argued that several core assumptions of rationalist-materialist approaches to IR theory impede understanding of the CCM's emergence, and thus the thesis adopts an interpretivist framework. The four chapters of Part II analyse international efforts on cluster munitions including prior, failed attempts to restrict cluster munitions, the emergence of an international campaign from 2003, ensuing activity involving states, international organisations and civil society, and the CCM's eventual negotiation involving more than 100 states. Part III marries this empirical account to theoretical analysis of four thesis propositions. It is concluded that non-state actor-engendered processes of evidence collection and analysis, learning and frame alignment were central to the Oslo process's emergence. The Oslo Declaration's particular humanitarian framing (to ban cluster munitions causing unacceptable harm to civilians) and the structure of the subsequent 'define-and-ban' discourse permitted convergence between states over prohibiting these weapons. Nevertheless, they contain implications for other international efforts aimed at controlling means of armed violence.
53

Investigation into the velocity distribution through an annular packed bed / Hendrik Jacobus Reyneke

Reyneke, Hendrik Jacobus January 2009 (has links)
The purpose of this study was to investigate the velocity distribution through an annular bed packed randomly with equal sized spheres. Extensive research has been conducted on the velocity distribution inside packed beds packed with equal sized spheres, different sized spheres, deformed spheres, cylinders and Raschig-rings. A majority of these experimental and numerical studies focused on the cylindrical packed bed. These studies and numerical models are all confined to the velocity profile once the fluid flow is fully developed. The development of the velocity through the inlet region of the bed and the fluid flow redistribution in the outlet of the bed is thus neglected. The experimental investigation into the velocity distribution down stream of the annular packed bed of the HTTU indicated that the velocity profile was independent of the mass flow rate for a particle Reynolds number range of 439 £ Re £ 3453 . These velocity profiles did not represent the distribution of the axial velocity due to shortcomings associated with the single sensor hot wire anemometry system used to measure the velocity distribution. A numerical investigation, using the RANS CFD code STAR-CCM+®, into the velocity distribution downstream of an explicitly modelled bed of spheres indicated that the axial velocity distribution could be extracted from the experimental velocity profiles by using an adjustment factor of 0.801. This adjusted velocity profile was used in the verification of the implicit bed simulation model. The implicit bed simulation model was developed in STAR-CCM+®. The resistance of the spheres was modelled using the KTA (1981) pressure drop correlation and the structure of the bed was modelled using the porosity correlation proposed by Martin (1978), while the effective viscosity model of Giese et al. (1998), adjusted by a factor of 0.8, was used to model the velocity distribution in the near wall region. It was found that the structure in the inlet region of the bed, where two walls disturb the packing structure, can be modelled as the weighted average of the radial and axial porosity while the structure in the outlet regions can be modelled by letting the radial porosity increase linearly to unity. The basic shape of the velocity profile is established immediately when the fluid enters the bed. The amplitude of the velocity peaks however increase in magnitude until the velocity profile is fully developed at a distance approximately of five sphere diameters from the bed inlet. The profile remains constant throughout the bed until the outlet region of the bed is reached. In the outlet region a significant amount of fluid redistribution is observed. The amplitude of the velocity peaks is reduced and the position of the velocity peaks is shifted inwards towards the centre of the annular region. The fully developed velocity profile, predicted by the simulation model is in good agreement with profiles presented by amongst others Giese et al. (1998). The current model however also offers insight into the development of the profile through the inlet of the bed and the fluid redistribution, which occurs in the outlet region of the bed. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2010.
54

Investigation into the velocity distribution through an annular packed bed / Hendrik Jacobus Reyneke

Reyneke, Hendrik Jacobus January 2009 (has links)
The purpose of this study was to investigate the velocity distribution through an annular bed packed randomly with equal sized spheres. Extensive research has been conducted on the velocity distribution inside packed beds packed with equal sized spheres, different sized spheres, deformed spheres, cylinders and Raschig-rings. A majority of these experimental and numerical studies focused on the cylindrical packed bed. These studies and numerical models are all confined to the velocity profile once the fluid flow is fully developed. The development of the velocity through the inlet region of the bed and the fluid flow redistribution in the outlet of the bed is thus neglected. The experimental investigation into the velocity distribution down stream of the annular packed bed of the HTTU indicated that the velocity profile was independent of the mass flow rate for a particle Reynolds number range of 439 £ Re £ 3453 . These velocity profiles did not represent the distribution of the axial velocity due to shortcomings associated with the single sensor hot wire anemometry system used to measure the velocity distribution. A numerical investigation, using the RANS CFD code STAR-CCM+®, into the velocity distribution downstream of an explicitly modelled bed of spheres indicated that the axial velocity distribution could be extracted from the experimental velocity profiles by using an adjustment factor of 0.801. This adjusted velocity profile was used in the verification of the implicit bed simulation model. The implicit bed simulation model was developed in STAR-CCM+®. The resistance of the spheres was modelled using the KTA (1981) pressure drop correlation and the structure of the bed was modelled using the porosity correlation proposed by Martin (1978), while the effective viscosity model of Giese et al. (1998), adjusted by a factor of 0.8, was used to model the velocity distribution in the near wall region. It was found that the structure in the inlet region of the bed, where two walls disturb the packing structure, can be modelled as the weighted average of the radial and axial porosity while the structure in the outlet regions can be modelled by letting the radial porosity increase linearly to unity. The basic shape of the velocity profile is established immediately when the fluid enters the bed. The amplitude of the velocity peaks however increase in magnitude until the velocity profile is fully developed at a distance approximately of five sphere diameters from the bed inlet. The profile remains constant throughout the bed until the outlet region of the bed is reached. In the outlet region a significant amount of fluid redistribution is observed. The amplitude of the velocity peaks is reduced and the position of the velocity peaks is shifted inwards towards the centre of the annular region. The fully developed velocity profile, predicted by the simulation model is in good agreement with profiles presented by amongst others Giese et al. (1998). The current model however also offers insight into the development of the profile through the inlet of the bed and the fluid redistribution, which occurs in the outlet region of the bed. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2010.
55

Guidelines and Criteria to Assess Singing and Music Training in Baccalaureate Music Theater Programs

Fleming-DeBerger, Rachelle 01 December 2011 (has links)
Within the last twenty years there have been a growing number of prospective students interested in pursuing musical theater (MT) training in colleges and universities throughout the United States. To meet this demand, the number of schools offering baccalaureate MT degrees has also grown. However, information on how to assess the music and singing training of undergraduate MT programs is not easily accessible to prospective undergraduate students. This is likely due to the fact that colleges and universities have only begun offering degrees in MT since 1970. Research-based information in this area is primarily found in peer-reviewed journals or by attending workshops presented by a few pedagogues specializing in MT vocal methods and techniques. The purpose of this essay is to develop criteria for assessing the singing and music training in MT baccalaureate degree programs that would be useful for prospective MT students, based on the current literature.
56

Bridging Component Models and Integration problems

Gelber, Natan January 2006 (has links)
Component based software engineering promotes the use of software component as a cor- ner stone for new software. Taken from other manufacturing fields, the vision of selecting the components needed and building them as Lego to create a new software seems to of- fer enormous advantages for software development. Worldwide, industry and scholars are trying to remove the obstacles obstructing this course of action. This report names some of the problems that software integrators and developers face. It concentrates on low-level communication and other aspects of integration problems. it is based upon practical and theoretical research. the conclusion of the report is that while each problem can be solved in and of itself, these solutions often lead to the creation of new problems, and therefore leave ample room for further research.
57

Controle de produção em uma indústria sucroalcooleira com CCM inteligente / Manufacturing control in a sugar and alcohol plant with intelligent MCC

Renan Piazzon Peres 02 October 2010 (has links)
Este trabalho tem como objetivo apresentar as características e conceitos da aplicação de centros de controle de motores inteligente, demonstrando as vantagens da utilização de rede industrial no controle da produção, especificamente o protocolo DeviceNet, e reunir em um documento as informações sobre a utilização e aplicações de diferentes configurações de acionamento e comando de motores instalados em um CCM. Para isso, foram realizados estudos e simulações de acionamentos elétricos protegidos por relés de sobrecarga em diferentes configurações de ligações e tecnologias utilizadas em instalações elétricas industriais, alterando os equipamentos, montagens e sinais recebidos para comando e proteção das cargas, bem como, observando os dados referentes aos custos de engenharia, instalação e materiais. Para as quatro opções analisadas foram estimados os tempos de projeto, instalação e valores estimados dos produtos e serviços necessários, fornecendo uma tabela comparativa entre as opções estudadas, além de concluir que o uso de CCM inteligente conectado ao aplicativo de supervisão IntelliCENTER se apresentou como a melhor solução, pois agrega as melhores características técnicas dos painéis elétricos, bem como a disponibilidade de monitoramento e controle da produção, com a utilização da rede DeviceNet. Além dos valores envolvidos na aquisição e startup, também foram observados os possíveis ganhos operacionais do sistema inteligente, pois permite via sistema supervisório os diagnósticos instantâneos, alarmes e desligamentos que localizam os defeitos nos acionamentos controlados. / This work aims to present the intelligent motor control center characteristics and concepts by showing the advantages of the industrial network application in the manufacturing control, more specific the DeviceNet protocol and gather in one document the information about the application and how to use different configurations of drivers and motor control installed in a MCC. In order to gather this information several studies and simulation were made by changing the equipment, assembling and signals in electric drivers protected by overload relays with different technologies and kind of connections used in industrial installations and comparing the engineering, assembling, and material costs. For the four analyzed options of drivers, the project development time, installation, product costs and necessary services were estimated showing a comparative table between options. This study will prove that the intelligent MCC connected to the IntelliCENTER software is the best solution because uses the best technical solution and also have the ability to monitor and control manufacturing, using DeviceNet network. Besides the acquisition and start up values it was also observed the operational benefits of the intelligent system, showing alarms, instantaneous diagnostics, and problems in the components of the controlled starter, by means supervisory system.
58

Exposure of Caco-2 cells to PFOS and PFOA

Neskovic, Anika January 2007 (has links)
The toxicity of perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) was measured. When Caco-2 cells from human adenocarcinoma are cultivated on a filter a monolayer is formed with properties similar to human duodenum epithelium. The Caco-2 cells grown on filter were exposed to the environmental contaminants PFOS and PFOA. The effects on the Caco-2 epithelium were examined by four different methods: trans-epithelial resistance (TEER), leakage of the intracellular protein lactate dehydrogenase (LDH), 14C-mannitol passage through the epithelium and protein content of the epithelium. TEER and C-mannitol passage show the Caco-2 cellmonolayer integrity, LDH leakage gives information of cytotoxicity and protein content of the epithelium shows cell adhension to the filter. In the first study TEER decreased at the highest concentrations of PFOS and PFOA (1Mm). The 14C-mannitol passage increased at the highest PFOS concentration. No cytotoxicity was shown and protein-loss was not observed. The second study with PFOS doses of 0, 1, 10, 100 and 500µM and 1 and 10mM showed that the effect of PFOS on TEER was dose-dependent. The 14C-mannitol passage was very high at the highest PFOS-concentration (10mM) and a dose-response was indicated. No cytotoxicity was demonstrated and protein-quantity was not affected. In the third study it was demonstrated that the toxicity of PFOS did not depend on the different concentrations of the oil-emulsion used to dissolve PFOS and PFOA.
59

Investigating the risk of intracranial haemorrhage or focal neurological deficit in adults diagnosed with cerebral cavernous malformation

Horne, Margaret Anne January 2015 (has links)
Background A cerebral cavernous malformation (CCM) is a small cluster of thin-walled, dilated blood vessels within the brain which is prone to bleed. Although the quantity of blood leaking tends to be small, even a small intracranial haemorrhage (ICH) can result in a clinically significant neurological deficit. Because some focal neurological deficits (FND) may in fact be haemorrhages that were undetected by imaging, FND were also included in the analysis wherever possible. In Scotland, between 2006 and 2010, the annual CCM detection rate was 0.8 per 100,000 people. Since estimates of prognosis inform decisions about whether to treat CCM, it is crucial that the untreated clinical course of the disease is fully understood. Aim The aims of this thesis are (i) to quantify the risk of ICH (or ICH or FND, referred to as ‘clinical event’) for an untreated adult within five years of CCM diagnosis, (ii) to identify prognostic factors for ICH (clinical event), and (iii) to create a model to predict, at the time of diagnosis, an individual’s risk of a subsequent ICH (clinical event). Methods Initially, a literature review was undertaken. Then data from adults diagnosed with CCM in the Scottish Intracranial Vascular Malformation Study (SIVMS) were analysed. SIVMS is a prospective, population-based cohort study: it includes all adults resident in Scotland at the time of diagnosis of a first-ever intracranial vascular malformation during the two five-year periods 1999–2003 and 2006–2010. Time-to-event methods were employed to compare the estimated risk of ICH (clinical event) for those who experienced a first ICH (clinical event) during untreated five-year follow-up with those who experienced a second ICH (clinical event). A statistical challenge when analysing clinical outcomes from patients with CCM is that the outcome event of ICH or FND is comparatively rare; therefore a larger cohort of CCM patients was required to identify more robustly potential predictors of ICH (clinical event) and to create a prognostic model to predict, at the time of diagnosis, an individual’s risk of a subsequent ICH (clinical event). Three research groups agreed to contribute their data to enable an individual patient data meta-analysis (IPDMA) to be undertaken. Results In the two SIVMS cohorts, 136 (1999–2003) and 165 adults (2006–2010) were diagnosed with CCM. In the earlier cohort, the estimated risk of a first ICH within five years of presentation (2.4%, 95% CI 0.0% to 5.7%) was significantly lower (p < 0.0001) than the risk of a recurrent ICH (31.9%, 95% CI 4.5% to 59.3%), but the annual risk of a recurrence declined over the five-year period. In the same cohort, women had an increased risk of a second clinical event (log-rank χ2(1) = 6.2, p = 0.01). The IPDMA was based on 988 adults, 62 of whom suffered a first ICH within five years of CCM diagnosis. When the data were pooled, the estimated adjusted hazard ratio for first ICH for clinical presentation (ICH/FND vs other presentation) was 4.5 (95% CI 1.5 to 13.4) and for brainstem location (brainstem vs other location) the adjusted hazard ratio was 3.3 (95% CI 1.5 to 7.2); age, sex and CCM multiplicity did not add any additional prognostic information. Conclusion In this thesis two risk factors have been identified that are independently associated with increased likelihood of experiencing an ICH (or clinical event) within five years of diagnosis. A prognostic model has been built and evaluated, based on these factors. Other areas to be explored in the future include external validation of the model and investigating the effects of (i) antithrombotic therapy and (ii) pregnancy on the progression of the disease.
60

CFD Validation of Flat Plate Film Cooling of Cylindrical and Shaped Holes Using RANS and LES Computational Models

Sudesh, Akshay 04 October 2021 (has links)
No description available.

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